package com.jiangruan.javaproject.request;



import java.io.*;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.Map;
import java.util.Set;

/**
 * @author:zengguanlin
 * @email:zengguanlin@2977725281@qq.com
 * @desc: 该类用于封装提供网络请求的功能代码，用于发起网络请求，并将网络的数据进行返回
 * @datatime: 2021/12/20 15:11
 */
public class HttpUtils {
    /**
     * 该函数用于实现get请求，并将请求的结果进行返回
     * @param path 请求的资源路径
     * @return 请求的结果
     */
    public static String get(String path ){
        InputStream inputStream = null;
        InputStreamReader inputStreamReader = null;
        BufferedReader reader = null;
        String line = "";//最开始空行
        String result = "";//每次读取到以后都要累计起来的读取结果
        try{
            //Union Resource Location 统一资源定位
           // URL url = new URL(path);
            URL url = new URL(path);
            URLConnection connection = url.openConnection();
            //进行连接
            connection.connect();
            inputStream = connection.getInputStream();
            //字符流：按行读
            inputStreamReader = new InputStreamReader(inputStream);
            reader = new BufferedReader(inputStreamReader);
            /*String line = reader.readLine();
            while (line != null){
                reader.readLine();
            }*/
            while ((line = reader.readLine()) != null){
                result += line;
            }
        }catch (MalformedURLException e){
            e.printStackTrace();
        }catch (IOException e){
            e.printStackTrace();
        }finally {
            //关闭读取流
            try{
                if(reader != null){
                    reader.close();
                }
                if (inputStreamReader != null){
                    inputStreamReader.close();
                }
                if (inputStream != null){
                    inputStream.close();
                }
            }catch (IOException e){
                e.printStackTrace();
            }
        }
        return result;
    }

    /**
     * 封装的用Java实现的原生post请求
     * @param path 请求的路径
     * @param header 请求头设置信息
     * @param data 请求数据
     * @return 请求的响应结果
     */

    public static String post(String path, Map<String, String> header, byte[] data) {
        OutputStream outputStream = null;
        BufferedReader reader = null;
        //result表示最后要返回的数据
        String result = "";

        try {
            URL url = new URL(path);
            HttpURLConnection conn = (HttpURLConnection) url.openConnection();//自动装箱
            conn.setRequestMethod("POST");
            //设置可以发送数据和接收数据
            conn.setDoInput(true);
            conn.setDoOutput(true);

            //设置请求头的属性
            //ContentType:application/json
            //Authorization:"Basic "+ base64(用户信息)
            if (!header.isEmpty()) {//isEmpty():空
                //将header中的数据遍历设置到请求头当中
                //如何遍历map
//                String value = header.get("key");
                //如何拿到map中所有的key
                Set<String> keys = header.keySet();//keyset集合
                //如何遍历set?foreach;迭代器
                for (String key : keys) {
                    String value = header.get(key);
                    conn.setRequestProperty(key, value);
                }
            }

            conn.connect();

            //把请求数据发送到请求的服务端上
            outputStream = (OutputStream) conn.getOutputStream();
            outputStream.write(data);
            outputStream.flush();

            //等待接受返回的数据
            reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
            String Line = null;
            while ((Line = reader.readLine()) != null) {
                result += Line;
            }

        } catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (reader != null) {
                    reader.close();
                }
                if (outputStream != null) {
                    outputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return result;
    }
}
